str1 = "Hello"
str2 = "World!"
str3 = "Python"
str7 = "My name is Tom, age is 24, classmeat is 24 grade"
str4 = str1.join(str2) # 将
print(str4)

str5 = str3.split(",")
print(str5)

str6 = str7.split(",")
print(str6)
